Luth-AR Stripped A2 Upper Receiver w/ Rear Sight Cut AR-15 5.56x45mm NATO/ .223 7.75in Length 7075-T6 Aluminum Anodized Black. Features shell deflector forward assist housing and provisions for installing an ejection port cover. Precision machined from a premium-grade 7075 T6 aluminum forging and hardcoat anodized for extra strength with a tough scratch-resistant Teflon coating. Does Not feature M4 Style Cuts. Specifications for Luth-AR Stripped A2 Upper Receiver w/ A2 Rear Sight Cut: Manufacturer: Luth-AR Color: Black Finish: Type III Hard Coat Anodized Fabric/Material: 7075-T6 Aluminum Caliber: 5.56x45mm NATO .223 Remington Gun Model: AR-15 Condition: New Last Chance: Yes Weight: 8.4 oz Height: 4 in Width: 2 in Length: 7.75 in Package Contents: Luth-AR Stripped A2 Upper Receiver w/ A2 Rear Sight Cut What firearm models does the manufacturer say Luth-AR Stripped A2 Upper Receiver w/ A2 Rear Sight Cut is compatible with? The manufacturer says that Luth-AR Stripped A2 Upper Receiver w/ A2 Rear Sight Cut is compatible with AR-15Luth-AR UR-A2-S: Stripped A2 Upper Receiver w/ Rear Sight Cut AR-15 5.56x45mm NATO/ .223 7.75in Length 7075-T6 Aluminum Anodized Black